<?php
if(!empty($_GET['lang']))
{
    $lang = $_GET['lang'];
    setcookie("lang_vinastemcelllab", $lang, time()+3600*24*7);
}
if(empty($_COOKIE['lang_vinastemcelllab']))
{
    setcookie("lang_vinastemcelllab", "vi", time()+3600*24*7);
}

header("Location: " . $_SERVER['HTTP_REFERER']);